Something I worry about: is how any position that is not extreme will get invariably get “primaried” by those with more extreme positions in any online debate. 

They will attract more energy , easier to get social capital and also plays well to most online algorithms. 

Having the center get and hold energy seems an unsolved problem.

This is only true for large spaces. It doesn't happen if you're at dinner with 10 friends or in that telegram group of 20 people you know.

That's why I believe the future of the internet is small groups of connected people.